Orientation Distribution in Bi_2Te_3-based Compound Prepared by Spark Plasma Sintering

摘要

P-type Bi_(0.5)Sb_(1.5)Te_3 compounds doped with 3wt.% Te were fabricated by spark plasma sintering after mixing large powders (P_L) and small powders(P_s). We obtained the highest figure of merit(Z_c) of 2.89X10~(-3)/K in sintered compound mixed to P_L:P_s=80:20. This resulted from the increase of orientation by large powders (P_s) and the reduction of pores by small powders. The figure of merit(Z_c) of the sintered compound using only small powders (P_s) showed a lower value of 2.67 X 10~(-3)/K compared with that of sintered compound mixed to P_L:P_s=80:20 owing to the increase of electrical resistivity.